1. Field of the Invention
The present invention relates to methods and apparatuses for determining organic component concentrations in an electrolytic solution, and more specifically to determination of organic component concentrations in a copper electroplating solution.
2. Description of the Related Art
In electrochemical deposition (ECD) process, the rigorous control of the relative proportions of respective inorganic and organic ingredients in the ECD bath is critical to the achievement of satisfactory results in the rate of metal film formation and the quality of the film so formed. During the use of the plating bath solution, the plating process may be affected by depletion of inorganic components and organic additives as well as by organic byproduct formation. The ECD bath chemistry therefore must be maintained by periodic replacement of a part or the entire ECD bath. It is therefore important to continuously or periodically monitor the concentrations of inorganic and/or organic components in the ECD bath, and responsively add respective components to the bath to maintain the composition of the bath in an effective state for the electrochemical deposition operation.
It is therefore one object of the present invention to provide an improved method for measuring concentrations of one or more organic components in an ECD bath.
Other objects and advantages will be more fully apparent from the ensuring disclosure and appended claims.